The invention relates to a hybrid circuit comprising a plate-shaped ceramic circuit substrate which can be vertically mounted on a mother board and on which is provided, near a lower edge, a series of contact areas (solder pads) for contacting the circuit with terminals of the mother board.
Mounting in particular of single-in-line hybrid assemblies on a mother board (substrate) still today is frequently carried out by through-mounting, even if the hybrid circuit proper or its surroundings on the mother board are otherwise designed in the known SMD technology. For establishing contact on the circuit board, the hybrid circuits are mostly provided with a so-called terminal comb that is slid onto the face side (i.e. onto the two lower edges of the circuit substrate). Said comb, towards the hybrid circuit, mostly consists of pocket-shaped terminals which, mostly on one side, abut a solder pad and are soldered to the same, cp. EP 0 148 461 B1, incorporated herein by reference. On the circuit board side, these terminals or terminal pins are formed, for example, with a V-shaped point for through-mounting.
In case of high pin density of the terminal comb, there are frequently problems arising because of too small pad dimensions and a too low amount of solder material available in connection therewith.
It is the object of the present invention to create relief in this respect, without the mounting operation being rendered more complex.
With a hybrid circuit of the type indicated at the out-set, this object is met in that the contact areas each extend down as far as the lower edge, and in that there is provided one recess each which forms a solder deposit and which extends through the circuit substrate and runs from the lower end face of the circuit substrate up into the respective contact area.
According to a development of the invention, elongate terminals can be provided, the one end thereof being adapted to be connected to a contact location of the mother board and the opposite end thereof being soldered to at least one contact area via a pocket-shaped terminal contour extending around the lower edges of the circuit substrate.